# Scaling DTChull tutorial to fullscale ship

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 July 6, 2016, 03:30 Scaling DTChull tutorial to fullscale ship #1 New Member   OFN Join Date: Jul 2016 Posts: 4 Rep Power: 8 Hi, I am having difficulties running InterDyMFoam on a full scale vessel (50m ~ 2000 t). I have meshed a 50m hull and enviroment. The mesh seems to be good since it is running nicely in InterFoam. I have use the DTChull tutorial as a basis, changing the hull and mesh, and scaled the values and parameters. The issue: Ship pitches/bow dives too much. How would you scale the different parameters from DTChull to a fullscale ship of 50m and 2000 tonn? I have tried tuning the rotational- and translationalDamper also the accelerationRelaxation to some extent but since the case has to compute for a while before I can inspect (if the ship overpitches or not) i havent testet more than a couple of combinations. Hopefully some of you have experience with scaling the DTChull. I have written a post on this here where my modified DTChull files are uploaded: (The mesh is not included due to a confidential hull) http://www.cfd-online.com/Forums/ope...e-problem.html Thanks

 July 6, 2016, 05:36 Problem solved #2 New Member   OFN Join Date: Jul 2016 Posts: 4 Rep Power: 8 Well... we found the source of the problem, and its embarrassingly simple! We have run a spilt hull with symmetry and forgot to divide the mass in two...! Also the intertia values are to high. Which explains it all... The changes in dampers and accelerationrelaxation etc.. just slowed down the motions. Still it would be interesting to know what parameters you use/would use in the dynamicMeshDict for a full scale ship of 50m and 2000t. Espessially these: - accelerationRelaxation - translationDamper - rotationDamper Should they be scaled and how?

 September 22, 2016, 13:06 #3 New Member   Nemo Join Date: Jul 2016 Posts: 5 Rep Power: 8 Dear OFNoob Did you find the answer? .I am also working on industrial project. I have 50m ship to simulate in OpenFoam. EmaManu likes this.

 August 29, 2017, 17:00 further resolutions? #4 New Member   Wendell Olson Join Date: Aug 2017 Posts: 1 Rep Power: 0 Dear Nemo did you find the answers or get additional info on this resolution? Thank you, EmaManu likes this.

 Tags dtchull, interdymfoam, scaling